Early 273 intake compatibility

By research I mean reading what people who have used the Modman have encountered. On a typical street engine (typical?- 350-400hp ish) the power down low and in the midrange is not there. But that should not be a surprise when looking at the design. It sure does look fantastic and has the options to run dual 4s, six pack or blower.
Can you please share that research?

modman no top.jpg